Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43.857
Filtrar
1.
Sci Rep ; 12(1): 8607, 2022 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-35597783

RESUMEN

Re-operation due to disease being inadvertently close to the resection margin is a major challenge in breast conserving surgery (BCS). Indocyanine green (ICG) fluorescence imaging could be used to visualize the tumor boundaries and help surgeons resect disease more efficiently. In this work, ICG fluorescence and color images were acquired with a custom-built camera system from 40 patients treated with BCS. Images were acquired from the tumor in-situ, surgical cavity post-excision, freshly excised tumor and histopathology tumour grossing. Fluorescence image intensity and texture were used as individual or combined predictors in both logistic regression (LR) and support vector machine models to predict the tumor extent. ICG fluorescence spectra in formalin-fixed histopathology grossing tumor were acquired and analyzed. Our results showed that ICG remains in the tissue after formalin fixation. Therefore, tissue imaging could be validated in freshly excised and in formalin-fixed grossing tumor. The trained LR model with combined fluorescence intensity (pixel values) and texture (slope of power spectral density curve) identified the tumor's extent in the grossing images with pixel-level resolution and sensitivity, specificity of 0.75 ± 0.3, 0.89 ± 0.2.This model was applied on tumor in-situ and surgical cavity (post-excision) images to predict tumor presence.


Asunto(s)
Neoplasias de la Mama , Verde de Indocianina , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Femenino , Fluorescencia , Formaldehído , Humanos , Márgenes de Escisión , Mastectomía Segmentaria/métodos , Imagen Óptica/métodos
2.
Acta Crystallogr D Struct Biol ; 78(Pt 5): 599-612, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35503208

RESUMEN

Anthozoan chromoproteins are highly pigmented, diversely coloured and readily produced in recombinant expression systems. While they are a versatile and powerful building block in synthetic biology for applications such as biosensor development, they are not widely used in comparison to the related fluorescent proteins, partly due to a lack of structural characterization to aid protein engineering. Here, high-resolution X-ray crystal structures of four open-source chromoproteins, gfasPurple, amilCP, spisPink and eforRed, are presented. These proteins are dimers in solution, and mutation at the conserved dimer interface leads to loss of visible colour development in gfasPurple. The chromophores are trans and noncoplanar in gfasPurple, amilCP and spisPink, while that in eforRed is cis and noncoplanar, and also emits fluorescence. Like other characterized chromoproteins, gfasPurple, amilCP and eforRed contain an sp2-hybridized N-acylimine in the peptide bond preceding the chromophore, while spisPink is unusual and demonstrates a true sp3-hybridized trans-peptide bond at this position. It was found that point mutations at the chromophore-binding site in gfasPurple that substitute similar amino acids to those in amilCP and spisPink generate similar colours. These features and observations have implications for the utility of these chromoproteins in protein engineering and synthetic biology applications.


Asunto(s)
Péptidos , Fluorescencia , Proteínas Luminiscentes/química , Péptidos/química
3.
J Phys Chem A ; 126(18): 2788-2793, 2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-35502941

RESUMEN

H2S is an important signal molecule in living systems and related with many physiological processes and diseases. Rapid detection of H2S, hence, is important for studying physiological processes and early diagnosis of diseases. Deep insight into the sensing mechanism is significant and inspiring for the design and modification of high-efficiency H2S probes. The current study has theoretically investigated the recognition and fluorescence mechanism of a newly reported high-efficiency H2S probe. The recognition mechanism is determined to be the reaction between the probe and HS- anion, the rationality of which is further confirmed from the fluorescence property of the recognition product. The non-fluorescence property of the probe attributes to a photoinduced electron transfer process, and the turn-on fluorescence upon exposure to H2S exhibits an intramolecular charge transfer property according to frontier molecular orbital analysis.


Asunto(s)
Colorantes Fluorescentes , Sulfuro de Hidrógeno , Transporte de Electrón , Fluorescencia , Sulfuro de Hidrógeno/análisis
4.
Anal Chim Acta ; 1208: 339825, 2022 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-35525587

RESUMEN

Atherosclerosis (AS) is the main cause of coronary heart disease, cerebral infarction and peripheral vascular disease, which is an important disease threatening human health. Abnormal levels of protein phosphorylation are closely related to the occurrence and development of diseases. Herein, the ratiometric fluorescence nanosensor (PCN/W- B@BSA) was prepared by using metal-organic frameworks (PCN-224) and fluorescent nanocluster wool-balls, which was applied for ratiometric fluorescence imaging of protein phosphorylation level in the AS mice model. Specific recognition of phosphorylation sites was achieved via specific interaction between active center Zr(IV) and phosphate. Using the two-photon property of porphyrin, the background is significantly reduced, and the sensitivity of imaging analysis is improved by combining with ratio imaging. Bovine serum albumin (BSA) was used to modify the surface of the nanosensor to reduce the non-specific adsorption and improve the biocompatibility of the nanosensor. Finally, the fluorescence nanosensor was successfully apply to fluorescence imaging of protein phosphorylation level in AS mice model, and the results showed that the protein phosphorylation level in the AS mice model was lower than that of the normal mice. The present study provides suitable fluorescence tool for further revealing phosphorylation related signaling pathways and disease mechanisms.


Asunto(s)
Aterosclerosis , Técnicas Biosensibles , Animales , Aterosclerosis/diagnóstico por imagen , Fluorescencia , Colorantes Fluorescentes , Ratones , Fosforilación , Carbonitrilo de Pregnenolona , Albúmina Sérica Bovina , Espectrometría de Fluorescencia/métodos
5.
Sci Rep ; 12(1): 7345, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35513504

RESUMEN

Extracted Mango and Orange juices were investigated by using spectroscopic techniques such as UV/Visible and Fluorescence. Three portions of samples (fresh juice) were stored at 22 °C for eight days, stored in a water bath and heated at 40 °C, 60 °C, and 80 °C for ten minutes. The highest wavelengths (455 nm) were observed from the UV/Vis results for fresh Mango juices, while 270 nm and 460 nm were observed for stored Mango juices. Furthermore, wavelengths of 320 nm were observed in heat-treated mango juice (40 °C). No absorption peaks were observed at 60 °C and 80 °C due to temperature effects. Absorption peaks of fresh fruit were observed at 330 nm and 390 nm, while 260 nm and 320 nm reflect stored orange juices absorptions peaks. From heat-treated stored (40 °C and 60 °C) samples, 320 nm and 260 nm absorption peaks were observed, respectively. Wavelength observed (454 nm, 540 nm & 700 nm) peaks represent the fresh mango juice spectra, while 460 nm and 700 nm are for stored Mango juices. The peaks observed in the region of 400-500 nm and at 700 nm represent heat-treated mango juices at 40 °C. Heat stored Mango juices (60 °C & 80 °C) have peaks at 700 nm. Peaks observed at 700 nm, 500 nm, and 455 nm reflect fresh orange juice, while 460-500 nm and 700 nm represent the emission spectra of the samples. The stored orange juice peaks at 460-500 nm and at 700 nm, but heated-stored orange juice peaks only at 700 nm. The pH values for orange and mango juices were 3.52-3.73 and 4.02-4.72, respectively.


Asunto(s)
Citrus sinensis , Mangifera , Bebidas/análisis , Fluorescencia , Frutas/química , Jugos de Frutas y Vegetales
6.
Bioorg Med Chem Lett ; 68: 128762, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35490954

RESUMEN

γ-glutamyl transpeptidase (GGT) is a kind of cell-surface enzyme that is overexpressed in many cancer cells. It is of great significance to develop an ideal tool for the diagnosis of GGT-rich cancer cells. Here, we reported a simple-structured but effective imaging probe for the detection of GGT activity. In the presence of GGT, the γ-glutamyl linkage could be cleaved specifically to produce amino-substituted product, resulting in significant fluorescence enhancement at 578 nm. Moreover, we successfully employed the probe to monitor GGT activity in HepG2 cells. We envisaged that such a simple but effective imaging tool could improve the practical applications for bioimaging.


Asunto(s)
Colorantes Fluorescentes , gamma-Glutamiltransferasa , Fluorescencia , Células Hep G2 , Humanos , Agua
7.
J Phys Chem A ; 126(19): 2899-2908, 2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35502789

RESUMEN

The ability to tune the optoelectronic properties of quantum dots (QDs) makes them ideally suited for the use as fluorescence sensing probes. The vast structural diversity in terms of the composition and size of QDs can make designing a QD for a specific sensing application a challenging process. Quantum chemical calculations have the potential to aid this process through the characterization of the properties of QDs, leading to their in silico design. This is explored in the context of QDs for the fluorescence sensing of dopamine based upon density functional theory and time-dependent density functional theory (TDDFT) calculations. The excited states of hydrogenated carbon, silicon, and germanium QDs are characterized through TDDFT calculations. Analysis of the molecular orbital diagrams for the isolated molecules and calculations of the excited states of the dopamine-functionalized quantum dots establish the possibility of a photoinduced electron-transfer process by determining the relative energies of the electronic states formed from a local excitation on the QD and the lowest QD → dopamine electron-transfer state. The results suggest that the Si165H100 and Ge84H64 QDs have the potential to act as fluorescent markers that could distinguish between the oxidized and reduced forms of dopamine, where the fluorescence would be quenched for the oxidized form. The work contributes to a better understanding of the optical and electronic behavior of QD-based sensors and illustrates how quantum chemical calculations can be used to inform the design of QDs for specific fluorescent sensing applications.


Asunto(s)
Puntos Cuánticos , Dopamina , Transporte de Electrón , Fluorescencia , Colorantes Fluorescentes , Puntos Cuánticos/química
8.
J Synchrotron Radiat ; 29(Pt 3): 807-815, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35511013

RESUMEN

X-ray fluorescence microscopy performed at nanofocusing synchrotron beamlines produces quantitative elemental distribution maps at unprecedented resolution (down to a few tens of nanometres), at the expense of relatively long measuring times and high absorbed doses. In this work, a method was implemented in which fast low-dose in-line holography was used to produce quantitative electron density maps at the mesoscale prior to nanoscale X-ray fluorescence acquisition. These maps ensure more efficient fluorescence scans and the reduction of the total absorbed dose, often relevant for radiation-sensitive (e.g. biological) samples. This multimodal microscopy approach was demonstrated on human sural nerve tissue. The two imaging modes provide complementary information at a comparable resolution, ultimately limited by the focal spot size. The experimental setup presented allows the user to swap between them in a flexible and reproducible fashion, as well as to easily adapt the scanning parameters during an experiment to fine-tune resolution and field of view.


Asunto(s)
Holografía , Microscopía , Nervio Sural , Sincrotrones , Fluorescencia , Humanos , Microscopía/métodos , Microscopía Fluorescente , Radiografía , Nervio Sural/diagnóstico por imagen , Rayos X
9.
Inorg Chem ; 61(20): 8015-8021, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35544341

RESUMEN

The rapid detection of antibiotics in agricultural products is of great significance. In this work, two stable fluorescent metal-organic frameworks (MOFs), BUT-178 and BUT-179, are synthesized and used to detect tetracycline antibiotics. Among them, BUT-179 exhibits better performance in the detection of different tetracycline antibiotics in water and eggs. The limits of detection of BUT-179 toward tetracycline, aureomycin, oxytetracycline, and doxycycline all reach the nanomolar level. Furthermore, the cycling tests confirm that BUT-179 can be easily recovered and repeatedly used without an obvious performance loss. This work demonstrates the excellent application potential of MOFs for food safety, especially the fluorescence detection of antibiotics in foods.


Asunto(s)
Compuestos Heterocíclicos , Estructuras Metalorgánicas , Antibacterianos/farmacología , Colorantes , Fluorescencia , Tetraciclina
10.
World J Gastroenterol ; 28(12): 1284-1287, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35431511

RESUMEN

Near infrared fluorescence using indocyanine green is beneficial for visual assessment of blood vessels, blood flow, and tissue perfusion, sentinel lymph node biopsy, lymph node road mapping, identification of the vascular system round the major vessels, and the detection of ureters in order to reduce the risk of iatrogenic ureteral lesions in colorectal surgery.


Asunto(s)
Cirugía Colorrectal , Procedimientos Quirúrgicos del Sistema Digestivo , Ganglio Linfático Centinela , Fluorescencia , Humanos , Verde de Indocianina , Imagen Óptica/métodos , Biopsia del Ganglio Linfático Centinela/métodos
11.
J Phys Chem B ; 126(15): 2921-2929, 2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35394770

RESUMEN

Alkyl chain-resulted odd-even effects in fluorescence quantum yield (FLQY) have also been reported in organic luminescent materials (OLMs). However, the odd-even effects in FLQY caused by the alkyl substitutes in OLMs are generally very weak, with only single-digit differences. Here, we report a series of alkyl-substituted dual-state luminogens (DSEgens) showing extremely high solid-state FLQY in even-numbered analogues (>90% FLQY) and a dramatically pronounced odd-even effect in FLQY. The odd-even effect in FLQY is over 26% alternation, and a maximum of 48% difference in FLQY was observed between the compounds C1 and C2 with a methyl and ethyl substitution, respectively. C1 and C2 also displayed a crystallochromy with a 22 nm difference in emission wavelength. In addition, odd-even effects in the melting point and decomposition temperature were also observed. With these bright DSEgens, applications such as specific recognition of picric acid and ultrasensitive trace water detection have been demonstrated.


Asunto(s)
Agua , Fluorescencia
12.
Soft Matter ; 18(16): 3125-3129, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35411907

RESUMEN

A novel helix hydrogel with a G-quartet structure was synthesized from guanosine (Gua) and its derivative 5'-guanosine monophosphate (5'-GMP) under a molecular crowding environment. The chirality of the hydrogel is adjusted by controlling the gelling speed. The chiral hydrogel can induce an achiral dye Thioflavin T (ThT) to realize circularly polarized fluorescence (CPL). The CPL dissymmetry factor |glum| of the dye-hydrogels can reach 3 × 10-2 and can be switched easily.


Asunto(s)
Hidrogeles , Luminiscencia , Fluorescencia
13.
Nat Commun ; 13(1): 1786, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379806

RESUMEN

Hydroxycinnamic acids present in plant cuticles, the interphase and the main protective barrier between the plant and the environment, exhibit singular photochemical properties that could allow them to act as a UV shield. Here, we employ transient absorption spectroscopy on isolated cuticles and leaf epidermises to study in situ the photodynamics of these molecules in the excited state. Based on quantum chemical calculations on p-coumaric acid, the main phenolic acid present in the cuticle, we propose a model in which cuticle phenolics display a photoprotective mechanism based in an ultrafast and non-radiative excited state deactivation combined with fluorescence emission. As such, the cuticle can be regarded as the first and foremost protective barrier against UV radiation. This photostable and photodynamic mechanism seems to be universal in land plants giving a special role and function to the presence of different aromatic domains in plant cuticles and epidermises.


Asunto(s)
Plantas , Rayos Ultravioleta , Fluorescencia , Fenoles , Hojas de la Planta/fisiología
14.
Methods Mol Biol ; 2430: 3-16, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35476322

RESUMEN

Filamentous microtubules, polymers of the heterodimeric protein tubulins play one of the major roles in the emergent nano-biotechnological devices. To develop the feature of those devices, it is important to understand the function of microtubule in in vitro, hence, the availability of purified αß-tubulin is required. Additionally, fluorescently labeled tubulin has become a powerful approach for extensively studying the dynamics of these components. In this chapter, the process of purifying the heterodimeric αß-tubulin from porcine brain will be described, as well as the process of labeling of the purified tubulin with fluorescence dye.


Asunto(s)
Colorantes Fluorescentes , Tubulina (Proteína) , Animales , Encéfalo/metabolismo , Fluorescencia , Colorantes Fluorescentes/metabolismo , Microtúbulos/metabolismo , Porcinos , Tubulina (Proteína)/metabolismo
15.
Mutat Res ; 824: 111779, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35472567

RESUMEN

Mismatch repair (MMR) is a highly conserved DNA repair pathway that corrects mismatched bases during DNA replication. The biological significance of MMR in human cells is underscored by the fact that dysfunction of the MMR pathway results in Lynch syndrome, which is associated with a genetic predisposition to different cancer types. We have previously established a reporter mismatch plasmid to evaluate MMR using fluorescent proteins in living cells. However, the preparation of these plasmids requires significant amounts of time and money, which reduces their broad applicability. To overcome the abovementioned limitations, we produced in this study a novel reporter plasmid, pBSII NLS-MC-EGFP-tdTomato (pBET2), that can be used in the oligo swapping method. In this method, a nicking endonuclease produces a single-stranded DNA gap on a double-stranded DNA plasmid that can be replaced by ligation with synthetic oligonucleotides. It is significantly easier and more user-friendly than previous assays, which require in vitro DNA synthesis with single-stranded plasmid DNA and purification using ultracentrifugation in cesium chloride-ethidium bromide gradients. The plasmid also contains a nicking site that allows the MMR repair machinery to efficiently distinguish the newly synthesized strand as a target for repair. In addition, a nuclear localization signal facilitates green fluorescent protein expression in the nucleus, which helps to verify the effectiveness of MMR using fluorescence microscopy. Similar to the previous reporter plasmid, this construct facilitates the assessment of MMR proficiency in human living cells via the expression of fluorescent proteins while overcoming many of the negative aspects of the previous protocol.


Asunto(s)
Reparación de la Incompatibilidad de ADN , Reparación del ADN , ADN/metabolismo , Fluorescencia , Humanos , Plásmidos/genética
16.
J Phys Chem B ; 126(16): 3048-3058, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35417173

RESUMEN

Mitochondrial membranes and their microenvironments directly influence and reflect cellular metabolic states but are difficult to probe on site in live cells. Here, we demonstrate a strategy, showing how the widely used mitochondrial membrane localization fluorophore 10-nonyl acridine orange (NAO) can be transformed into a multifunctional probe of membrane microenvironments by monitoring its blinking kinetics. By transient state (TRAST) studies of NAO in small unilamellar vesicles (SUVs), together with computational simulations, we found that NAO exhibits prominent reversible singlet-triplet state transitions and can act as a light-induced Lewis acid forming a red-emissive doublet radical. The resulting blinking kinetics are highly environment-sensitive, specifically reflecting local membrane oxygen concentrations, redox conditions, membrane charge, fluidity, and lipid compositions. Here, not only cardiolipin concentration but also the cardiolipin acyl chain composition was found to strongly influence the NAO blinking kinetics. The blinking kinetics also reflect hydroxyl ion-dependent transitions to and from the fluorophore doublet radical, closely coupled to the proton-transfer events in the membranes, local pH, and two- and three-dimensional buffering properties on and above the membranes. Following the SUV studies, we show by TRAST imaging that the fluorescence blinking properties of NAO can be imaged in live cells in a spatially resolved manner. Generally, the demonstrated blinking imaging strategy can transform existing fluorophore markers into multiparametric sensors reflecting conditions of large biological relevance, which are difficult to retrieve by other means. This opens additional possibilities for fundamental membrane studies in lipid vesicles and live cells.


Asunto(s)
Parpadeo , Cardiolipinas , Fluorescencia , Colorantes Fluorescentes , Cinética
17.
Head Neck ; 44(6): 1496-1499, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35366038

RESUMEN

In head and neck oncologic surgery a reconstructive phase is often required and pedicled flaps are still a viable option, though they may need a pedicle division performed at a later stage. Several techniques are commonly used for perfusion assessment of the flaps, with indocyanine green (ICG) fluorescence video-angiography representing a promising tool. We used ICG video-angiography to evaluate the perfusion of two of the most commonly adopted pedicled flaps in the head and neck field (the supraclavicular and the paramedian forehead flap) before and after second-stage pedicle division, allowing a safer in-setting. Moreover, the new high-resolution device that we have employed added further accuracy to the traditional video-angiography, providing a real-time flap-to-normal skin ICG ratio. Indeed, ICG video-angiography proved to be a useful tool in head and neck reconstructive surgery and it may allow an earlier second-stage pedicle division.


Asunto(s)
Verde de Indocianina , Procedimientos Quirúrgicos Reconstructivos , Angiografía/métodos , Fluorescencia , Humanos , Procedimientos Quirúrgicos Reconstructivos/métodos , Colgajos Quirúrgicos
18.
J Med Chem ; 65(8): 6056-6069, 2022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35427109

RESUMEN

The controlled release of a molecule of interest (MOI) is useful in probe design, prodrug construction, and drug delivery. We report herein a versatile thiol-triggered fluorogenic release system using the Baylis-Hillman (BH) adducts as a module. Common functional groups (e.g., amino, hydroxyl, carboxylic, and sulfhydryl groups) in a MOI are readily integrated into the module. The MOI release is fast (∼10 min) with a nearly quantitative yield and a >250-fold fluorescence increment. We further prepared two prodrugs to release camptothecin and nitric oxide (NO) using the two-photon excitable template, and the activation of prodrugs was visualized in live cells and mouse tissues. The therapeutic potential of the NO prodrug was also validated in a stroke model. This BH adduct-based fluorogenic release features multiple advantages, such as easy preparation, compatibility of various functional groups, fast response, high release yield, and tunable emission spectra, and is expected to have broad applications.


Asunto(s)
Profármacos , Animales , Camptotecina , Fluorescencia , Ratones , Compuestos de Sulfhidrilo
19.
J Biomed Opt ; 27(4)2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35460219

RESUMEN

SIGNIFICANCE: Dynamic diffuse fluorescence tomography (DFT) can recover the static distribution of fluorophores and track dynamic temporal events related to physiological and disease progression. Dynamic imaging indocyanine green (ICG) approved by the food and drug administration is still under-exploited because of its characteristics of low quantum yield and relatively rapid tissue metabolism. AIM: In order to acquire the ICG tomographic image sequences for pharmacokinetic analysis, a dynamic DFT system was proposed. APPROACH: A fiber-based dynamic DFT system adopts square-wave modulation lock-in photon-counting scheme and series-parallel measurement mode, which possesses high sensitivity, large dynamic range, high anti-ambient light ability in common knowledge, as well as good cost performance. In order to investigate the effectiveness of the proposed system, the measurement stability and the anti-crosstalk-a crucial factor affecting the system parallelization-were assessed firstly, then a series of static phantoms, dynamic phantoms and in vivo mice experiments were conducted to verify the imaging capability. RESULTS: The system has the limited dynamic range of 100 dB, the fluctuation of photon counting within 3%, and channel-to-channel crosstalk ratio better than 1.35. Under the condition of a sufficient signal-to-noise ratio, a complete measurement time for one frame image was 10.08 s. The experimental results of static phantoms with a single target and three targets showed that this system can accurately obtain the positions, sizes, and shapes of the targets and the reconstructed images exhibited a high quantitativeness. Further, the self-designed dynamic phantom experiments demonstrated the capability of the system to capture fast changing fluorescence signals. Finally, the in vivo experiments validated the practical capability of the system to effectively track the ICG metabolism in living mice. CONCLUSIONS: These results demonstrate that our proposed system can be utilized for assessing ICG pharmacokinetics, which may provide a valuable tool for tumor detection, drug assessment, and liver function evaluation.


Asunto(s)
Verde de Indocianina , Tomografía , Animales , Fluorescencia , Verde de Indocianina/farmacocinética , Ratones , Fantasmas de Imagen , Tomografía Computarizada por Rayos X
20.
Environ Sci Technol ; 56(8): 5081-5089, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35378039

RESUMEN

A combination of synchrotron radiation-based elemental imaging, in vivo redox status analysis, histology, and toxic responses was used to investigate the uptake, biodistribution, and adverse effects of Ce nanoparticles (CeO2 NP; 10 nm; 0.5-34.96 mg Ce L-1) or Ce(NO3)3 (2.3-26 mg Ce L-1) in Caenorhabditis elegans. Elemental mapping of the exposed nematodes revealed Ce uptake in the alimentary canal prior to depuration. Retention of CeO2 NPs was low compared to that of Ce(NO3)3 in depurated individuals. X-ray fluorescence (XRF) mapping showed that Ce translocation was confined to the pharyngeal valve and foregut. Ce(NO3)3 exposure significantly decreased growth, fertility, and reproduction, caused slightly reduced fecundity. XRF mapping and histological analysis revealed severe tissue deformities colocalized with retained Ce surrounding the pharyngeal valve. Both forms of Ce activated the sod-1 antioxidant defense, particularly in the pharynx, whereas no significant effects on the cellular redox balance were identified. The CeO2 NP-induced deformities did not appear to impair the pharyngeal function or feeding ability as growth effects were restricted to Ce(NO3)3 exposure. The results demonstrate the utility of integrated submicron-resolution SR-based XRF elemental mapping of tissue-specific distribution and adverse effect analysis to obtain robust toxicological evaluations of metal-containing contaminants.


Asunto(s)
Cerio , Nanopartículas del Metal , Nanopartículas , Animales , Caenorhabditis elegans , Fluorescencia , Humanos , Nanopartículas del Metal/toxicidad , Faringe , Sincrotrones , Distribución Tisular , Rayos X
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...